A karaoke device may have a function of analyzing and evaluating a singing voice in many cases. Various methods are used for singing evaluation. As one of the methods, a technique for comparing level data acquired from a voice of a singer with level data composing Musical Instrument Digital Interface (MIDI) messages of a reference singing sound included in original musical piece data and evaluating a singing in response to a difference therebetween is disclosed, for example, in Japanese Patent Application Laid-Open No. H10-49183.